Adds computed spool statistics to filament list:
- spool_count: Number of non-archived spools of this filament
- total_remaining_weight: Sum of remaining weight across all spools
Backend changes:
- Modified database/filament.py find() to compute stats via subquery
- Added fields to Filament pydantic model in api/v1/models.py
- Updated filament API endpoint to include stats in response
Frontend changes:
- Added fields to IFilament interface
- Added columns to filament list table
- Added translation keys
Closes#15
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>